UCL Experimental Particle Physics Consolidated Grant (2019-2022)

Lead Research Organisation: University College London
Department Name: Physics and Astronomy

Abstract

Experimental particle physics studies extremely small sizes, or equivalently extremely high energies. We are seeking to understand the underlying nature of the physical universe in terms of fundamental forces and particles to answer the simple question: how did our universe evolve to allow life.

Experiments capable of reaching these extremes of energy & size are very technically demanding. The challenges include devising precision detectors which can operate in hostile environments, particle accelerators which can collide beams at very high energies, super-sensitive detectors capable of identifying very rare decays, high-speed electronics which can read out millions of pieces of information per second & software which can analyse petabytes of data in a distributed fashion. Particle physics thereby stimulates a variety of important technological developments.

This is a "consolidated grant", underpinning the base of highly skilled research & technical staff which allows UCL to lead projects at the very highest levels. It provides the support that allows the group to effectively train PhD students & young post-doctoral researchers. The science this grant will support includes:

- Understanding the properties and exact nature of the Higgs boson, searching for evidence of new physics at the LHC, and upgrading the ATLAS experiment.
- Understanding why we live in a universe that is dominated by matter with only a tiny anti-matter component, in contrast to the conditions immediately following the Big Bang. We will study in detail the properties of the neutrino, which is a stable, uncharged, almost massless particle released in radioactive beta decays. The neutrino is being studied with the NOvA and CHIPS experiments, and in the near future with the massive DUNE experiment that we will be helping to construct. UCL will also be analysing data from the SuperNEMO experiment, which will search for the incredibly rare process whereby two simultaneous beta-decays occur inside the nucleus. Examining such decays will yield fundamental insights into the nature of the neutrino.
- Seeking evidence for the dark matter, that makes up the vast majority of the matter in the universe, with the LZ experiment that is sensitive to rare and absolutely tiny signatures that dark matter particles in our galaxy would leave if they were to bounce off regular atoms in the detector.
- Searching for phenomena at extremely high energies, well beyond the reach of man-made accelerators like the LHC. We are searching for the interactions of ultra-high energy neutrinos in the Antarctic ice using the ANITA experiment
- Looking for evidence of an exceedingly rare process whereby a muon (a heavier version of the electron) spontaneously converts into three electrons; observation of this process would be a clear indication of new physics not described in the Standard Model of particle physics.
- Developing new accelerator and detector technologies for future experiments. We need to build higher energy colliders, and giant detectors able to detect neutrino beams fired over large distances, as well as 10-times larger underground detectors to continue the search for rare processes. These crucial science goals require the realisation of new detectors with unprecedented performance and which can be scaled-up effectively and affordably.
- Sharing the results of our work with other scientists and industry. Our accelerator and radiation measurement expertise can be applied to the fields of nuclear medicine, security, and food safety. We also cooperate with instrument manufacturers in order to develop better products for our own research and for other scientific and industrial users.

Some of this work is funded by other grants but is underpinned by the technical expertise that is supported by this consolidated grant. Continuity & support for the technical base in the UCL High Energy Physics Group is vital to progress the science & the benefits that it brings.

Planned Impact

The UCL HEP Group has a demonstrable track record of realising impact through technology development with commercial and industrial partners; translational activities for medical treatment infrastructure and diagnostic techniques for major international health concerns; skills development for emerging market sectors; and public engagement. Our strategy directly supports 2 of the 10 pillars of the government's industrial strategy and one of it's Eight Great Technologies, and knowledge transfer aligned with the UK's impact agenda. Our activities include:

* developing proton range detectors for proton beam therapy cancer treatment centres. Through STFC Industrial Partnership and EU Marie Curie ITN grants we have achieved world-leading resolution (0.7%) at clinical facilities and, with industrial collaborators, are moving towards commercial development of a clinical device.

* leveraging our low-background expertise in dark matter and neutrinoless double beta decay searches to design a state-of-the-art gamma spectroscopy detectors with world-leading low-energy sensitivity installed at the Boulby Underground Laboratory, and development of cutting-edge mass spectrometry (ICP-MS) techniques with application to heavy metal toxicity. Both our gamma and ICP-MS research feature in a recent GCRF award to tackle lead poisoning and we are registering our facility as a National Reference Laboratory for the Food Standards Agency to perform measurements of hazardous heavy metals and contaminants to unprecedented sensitivity and accuracy.

* working with industry partners to improve the sensitivity of commercial surface radioactivity detectors and meet the growing requirements of the electronics packaging market sector in terms of alpha particle emission and subsequent single site effects.

* training and supervision of undergraduate, PhD students and RAs is helping to prepare the UK workforce for opportunities in the rapidly growing data science driven market sectors. We won the call to host STFC's first CDT for Data Intensive Science (DIS) and have partnerships with leading companies to address their real-world challenges now, whilst producing a skilled workforce for this key emerging area for the UK. We will host STFC's 1st dedicated summer school in DIS at UCL to further propagate our industry contacts and expertise.

* engaging with the public, industry and policy makers to explain the impact and value of fundamental research and to justify the funding of such research. We continue to work with key media outlets (Guardian, BBC, ITV, and others) to ensure accurate, intelligent discussion of science research is accessible to large audiences. A key aim of ours is to communicate the process of scientific exploration, the interpretation of data and uncertainties and confidence in conclusions. We have had significant success in this area, particularly through the regular columns by Butterworth for the Guardian, and publication of popular science books such as "The Particle Zoo" (Hesketh), "A Map of the Invisible" (Butterworth) and "Inside CERN's Large Hadron Collider" (Campanelli).

Publications

10 25 50
 
Title "Axion Like Particle (ALP)" of "A search for new physics in low-energy electron recoils from the first LZ exposure" 
Description The observed 90% C.L. upper limit on axion like particle (ALP) coupling constant (g_{ae}) in SR1. ALP mass spanning from 1 keV to 17 keV is considered. The data contains observed upper limit, median sensitivity and 1\sigma and 2\sigma sensitivity range as a function of ALP Mass. 
Type Of Material Database/Collection of data 
Year Produced 2023 
Provided To Others? Yes  
URL https://www.hepdata.net/record/145868
 
Title "Data" of "First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment" 
Description Data points used in analysis in log_10(S2)-S1 space 
Type Of Material Database/Collection of data 
Year Produced 2023 
Provided To Others? Yes  
URL https://www.hepdata.net/record/145093
 
Title "Effective Neutrino Magnetic Moment" of "A search for new physics in low-energy electron recoils from the first LZ exposure" 
Description The observed 90% C.L upper limit on effective neutrino magnetic moment (\mu_{\nu}[\mu_{B}]) in SR1. The data contains observed upper limit, median sensitivity and 1\sigma and 2\sigma sensitivity range. 
Type Of Material Database/Collection of data 
Year Produced 2023 
Provided To Others? Yes  
URL https://www.hepdata.net/record/145865
 
Title "Effective Neutrino Milicharge" of "A search for new physics in low-energy electron recoils from the first LZ exposure" 
Description The observed 90% C.L upper limit on neutrino effective millicharge (\delta_{Q}[e_{0}]) in SR1. The data contains observed upper limit, median sensitivity and 1\sigma and 2\sigma sensitivity range. 
Type Of Material Database/Collection of data 
Year Produced 2023 
Provided To Others? Yes  
URL https://www.hepdata.net/record/145866
 
Title "Efficiency" of "First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment" 
Description Data selection efficiency as a function of nuclear recoil energy 
Type Of Material Database/Collection of data 
Year Produced 2023 
Provided To Others? Yes  
URL https://www.hepdata.net/record/145092
 
Title "Electronic Recoil Efficiency" of "A search for new physics in low-energy electron recoils from the first LZ exposure" 
Description Electronic Recoil (ER) detection efficiency evaluated as a function of simulated true ER energy [keVee]. The data contains ER detection efficiency for ROI of study. 
Type Of Material Database/Collection of data 
Year Produced 2023 
Provided To Others? Yes  
URL https://www.hepdata.net/record/145864
 
Title "Hidden Photon (HP)" of "A search for new physics in low-energy electron recoils from the first LZ exposure" 
Description The observed 90% C.L. upper limit on hidden photon (HP) coupling constant squared (\kappa^2) in SR1. HP mass spanning from 1 keV to 17 keV is considered. The data contains observed upper limit, median sensitivity and 1\sigma and 2\sigma sensitivity range as a function of HP Mass. 
Type Of Material Database/Collection of data 
Year Produced 2023 
Provided To Others? Yes  
URL https://www.hepdata.net/record/145869
 
Title "LZ SR1 Data" of "A search for new physics in low-energy electron recoils from the first LZ exposure" 
Description The SR1 data in the {S1c, log10S2c} space with respect to observed time. Top plot is first half of SR1 containing 178 of the final data set. Bottom plot is second half of SR1 containing 157 events. 
Type Of Material Database/Collection of data 
Year Produced 2023 
Provided To Others? Yes  
URL https://www.hepdata.net/record/145863
 
Title "SDn WIMP cross-section" of "A search for new physics in low-energy electron recoils from the first LZ exposure" 
Description The observed 90% C.L. upper limit for the spin-dependent WIMP cross-section (cm^2) vs. WIMP mass (GeV/c^2) for coupling on neutrons. The result is obtained for WIMPs undergoing the Migdal effect from 0.5 to 9 GeV/c2. The data contains observed upper limit, median sensitivity and 1\sigma and 2\sigma sensitivity range as a function of WIMP Mass. 
Type Of Material Database/Collection of data 
Year Produced 2023 
Provided To Others? Yes  
URL https://www.hepdata.net/record/145871
 
Title "SDn cross section" of "First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment" 
Description 90% CL WIMP SDn cross sections, including sensitivities and nuclear structure uncertainties 
Type Of Material Database/Collection of data 
Year Produced 2023 
Provided To Others? Yes  
URL https://www.hepdata.net/record/145090
 
Title "SDp WIMP cross-section" of "A search for new physics in low-energy electron recoils from the first LZ exposure" 
Description The observed 90% C.L. upper limit for the spin-dependent WIMP cross-section (cm^2) vs. WIMP mass (GeV/c^2) for coupling on protons. The result is obtained for WIMPs undergoing the Migdal effect from 0.5 to 9 GeV/c2. The data contains observed upper limit, median sensitivity and 1\sigma and 2\sigma sensitivity range as a function of WIMP Mass. 
Type Of Material Database/Collection of data 
Year Produced 2023 
Provided To Others? Yes  
URL https://www.hepdata.net/record/145872
 
Title "SDp cross section" of "First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment" 
Description 90% CL WIMP SDp cross sections, including sensitivities and nuclear structure uncertainties 
Type Of Material Database/Collection of data 
Year Produced 2023 
Provided To Others? Yes  
URL https://www.hepdata.net/record/145091
 
Title "SI WIMP cross-section" of "A search for new physics in low-energy electron recoils from the first LZ exposure" 
Description The observed 90% C.L. upper limit for the spin-independent (cm^2) WIMP cross-section vs. WIMP mass (GeV/c^2), using the Migdal signal pathway. The result is obtained for WIMPs undergoing the Migdal effect from 0.5 to 9 GeV/c2. The data contains observed upper limit, median sensitivity and 1\sigma and 2\sigma sensitivity range as a function of WIMP Mass. 
Type Of Material Database/Collection of data 
Year Produced 2023 
Provided To Others? Yes  
URL https://www.hepdata.net/record/145870
 
Title "SI cross section" of "First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment" 
Description 90% CL WIMP SI cross sections, including sensitivities 
Type Of Material Database/Collection of data 
Year Produced 2023 
Provided To Others? Yes  
URL https://www.hepdata.net/record/145089
 
Title "Solar Axion" of "A search for new physics in low-energy electron recoils from the first LZ exposure" 
Description The observerd 90% C.L upper limit on solar axion g_{ae} coupling constant in valid across the mass range for SR1. The data contains observed upper limit, median sensitivity and 1\sigma and 2\sigma sensitivity range as a function of Solar Axion Mass . 
Type Of Material Database/Collection of data 
Year Produced 2023 
Provided To Others? Yes  
URL https://www.hepdata.net/record/145867